High-efficiency gas furnaces, also known as condensing furnaces, condense the water vapor in exhaust gases to extract additional heat. This efficiency comes at a cost, however. Experts say a condensing furnace may cost about $1,000 more than a furnace with an annual fuel utilization efficiency (AFUE) rating of around 80 percent. Installation costs may be higher as well. However, because a condensing furnace will use less fuel over time, the energy savings may be enough to recoup the extra cost. In addition, a condensing furnace will emit less carbon dioxide, which may be an important factor for those concerned about pollution. A condensing furnace with an AFUE of 95 percent or more will qualify for a federal tax credit if installed by the end of 2011, and additional rebates may be available in certain areas. Experts generally say that in areas with harsh winters, such as the Northeast and Midwest, a high-efficiency furnace is worth the higher initial cost. In milder climates, an 80 percent AFUE furnace is likely to be more cost effective in the long run.
Several sources offer general information about energy-efficient furnaces and their potential cost savings. These include EnergySavers.gov, ConsumerReports.org, the American Council for an Energy-Efficient Economy and HomeTips.com. National Geographic's TheGreenGuide.com offers information about the environmental benefits of high-efficiency furnaces, while the Energy Star website, EnergyStar.gov, has information about federal tax credits and other rebates. An article from The Seattle Times offers specific tips for buying an energy-efficient furnace.
This article compares low-, mid-, and high-efficiency heating systems and offers advice on whether to choose a high-efficiency unit. A table shows the possible cost savings of replacing an older, inefficient furnace.
Review: Furnaces and Boilers, Editors of EnergySavers.gov, Updated Oct. 5, 2010
This buying guide discusses improvements in furnace efficiency over the years. It discusses the cost differences between high-efficiency furnaces and midrange furnaces and factors that may affect the payoff period for a higher-efficiency furnace. Unlike other content on this site, this article is available to nonsubscribers.
Review: Gas Furnace Buying Advice, Editors of ConsumerReports.org
This article touts the energy-saving benefits of high-efficiency furnaces. It discusses potential cost savings and benefits to the environment.
Review: Furnace Buying Guide, Tara Snyder, March 2010
4. American Council for an Energy Efficient Economy
Editors recommend high-efficiency furnaces, even for those living in milder climates. This site has lots of information relating to energy-efficient appliances and calculating your return on investment.
Review: Heating, Editors of American Council for an Energy-Efficient Economy
5. Seattle Times
Karen Youso outlines factors to consider when buying a high-efficiency furnace. She also discusses other useful features like sealed combustion and a variable-speed fan.
Review: 9 Things to Know Before Buying a Furnace, Karen Youso, Nov. 20, 2009
This page discusses the benefits of buying a high-efficiency furnace, including estimated cost information that is not available at other sites. However, because the article has no date, it is not clear whether this information is still accurate.
Review: High-Efficiency Furnaces: A Buying and Care Guide, Editors of HomeTips.com
This page has information about the federal tax credits for energy-efficient heating and cooling systems. Elsewhere on this site, readers can find a tool to research additional state and municipal rebates.
Review: Federal Tax Credits for Consumer Energy Efficiency, Editors of EnergyStar.gov